The Gambia's President Adama Barrow went into self-isolation on Wednesday, his office said, after the West African state's vice president tested positive for coronavirus.
In a statement published on social media, Barrow's office said the president will self-isolate for two weeks, with immediate effect.
"The public is reminded that the coronavirus is real and exists in The Gambia," the statement said.
It added that citizens should wear face masks and practise social distancing.
Health authorities in the former British colony of some two million people have recorded 326 coronavirus cases to date, with eight fatalities.
But as with other poor countries in the region, there are fears that the tiny country is ill-equipped for a large outbreak.